Question

The ratio of the third term and sixth term of an AP is 4:5.
Find x1:x11
If x11=60 then find x16

Answer 1

Let the first term be A and common difference be D

====》(3rd term):(6th term)=4:5

====》(a+2d)/(a+5d)=4:5

====》5a+10d=4a+2d

====》5a-4a=10d-2d

====》a=10d

THEREFORE

(7th term):(11th term)

===》(a+6d)/(a+10d)

===》(10d+6d):(10d+10d)

===》16d:20d

Answer:4:5